Devices, kits and methods relating to treatment of facet joints

ABSTRACT

A facet joint surgical tool for treating a facet joint synovial cyst includes rotatable members disposed side-by-side through a minimally invasive sheath and rotatable to reconfigure distal end portions between a facet joint penetration configuration with a tissue piercing tip and a facet joint retraction configuration. Facet joint synovial cysts located to an anterior side of the facet joint are treated by a posterior approach with access to the cyst through the facet joint retracted by the surgical tool. Facet joint synovial cysts located to a posterior side of the facet joint are treated by direct access from a posterior approach.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims a benefit of U.S. provisional patent applicationNo. 61/903,806 entitled “DEVICES, KITS AND METHODS RELATING TO TREATMENTOF FACET JOINTS” filed Nov. 13, 2013, each and every portion of which isincorporated herein by reference.

FIELD OF INVENTION

This invention relates to the spine and facet joints, including withrespect to minimally invasive procedures to treat facet joint synovialcysts, which may be image guided.

BACKGROUND OF INVENTION

Back pain is the commonest cause of disability. Approximately 40% ofback pain is caused by disorders of the facet joints.

The facet joints (also called zygapophysial joints or z-joints) arepaired structures on the back and side of the spine. These jointssupport the torso during flexion, extension and rotation of the spine.These are synovial joints and therefore contain joint fluid. Joint fluidis viscous and a lubricant. Synovial cysts occur along the margins ofmany joints in the body. These cysts are caused by a degenerativeprocess. Synovial cysts are lined by synovial cells.

These cysts frequently occur along the margins of the facet joint. Thesecysts may occur on the back (posterior) or the front (anterior) of thefacet joints. The sensitive nerve structures are located on the front ofthe joint and therefore anterior cysts located within the spinal canalare usually symptomatic. Cysts along the back of the joints may beassociated with back pain but are usually asymptomatic. When there is acyst on the back of the joint there is usually no anterior cyst present.This is believed to be due to relative decompression of the anteriorjoint capsule pressure into the posterior capsule.

When these cysts enlarge into the spinal canal they cause back painand/or radiculopathy (leg pain) by compressing the adjacent structuresand nerves. These benign cysts usually are connected to the adjacentjoint. In the spine these cysts usually arise from the facet joints butalso may occur within the spinal ligaments rarely.

Fluid, bone, cartilage fragments and debris are frequently present inarthritic joints. Synovial cysts arise from arthritic joints.

The current treatment of synovial cysts is usually surgical. During thesurgical procedure an incision is made in the back and the muscles andligaments are cut and retracted to access the back of the spinal canal.The lamina or back of the bony spinal canal is then removed in order toaccess the cyst. Then the cyst is surgically removed using a scalpel,cautery or other cutting instruments. The surgical procedure iseffective resulting in improvement in leg pain in the majority ofpatients. However surgery damages surrounding tissues, ligaments andmuscles. Also surgery can result in disability due to removal of ordamage to the muscle, ligaments and bony structures that mechanicallysupport the spine and may result in spinal instability. Although surgeryis usually successful cysts may recur even after a successful operation.A current trend in spinal surgery and intervention is toward tools andtechniques to minimize tissue damage using image guidance and minimallyinvasive techniques

Percutaneous aspiration is also used to treat synovial cysts, and inparticular synovial cysts located anterior to a facet joint. Instead ofdirectly removing the cyst the joint is aspirated with a needle.Synovial fluid is very thick and often cannot be aspirated using astandard spinal needle. The results of current percutaneous methods oftreatment are sub-optimal. Less than half of patients are successfullytreated. Also, even when successfully aspirated the cysts may refillwith joint fluid resulting in recurrence of symptoms. Therefore manypercutaneous aspirations fail to resolve the patient's symptoms andpatients often have to undergo a second open surgical procedure todefinitively treat their pain with additional risks, expense, recoverytime and pain. Direct percutaneous aspiration has traditionally not beenan option for synovial cysts located anterior to facet joints.

Percutaneous ablation is used to treat facet related pain but is notused to treat facet cysts. A common method to treat facet related painis radiofrequency ablation. The nerves supplying the facet joint areheated and this disrupts the nerve function and conduction resulting inpain relief. Also the capsule may be treated directly for treating pain.Radiofrequency energy delivered by a needle or probe is usually used forablation although cooled probes (cryotherapy), focused ultrasound andalcohol may also be used.

There is a need for percutaneous minimally invasive devices andprocedures to access the facet joint and perform various procedures inrelation to the facet joint, for example to aspirate thick synovialfluid and definitively treat synovial cysts of the facet joints.

SUMMARY OF INVENTION

Various aspects of the invention are disclosed herein. Disclosed aretools, kits, methods and systems to access the facet joint and to permitmedical procedures to be performed in the vicinity of the facet joint,for example to treat facet joint synovial cysts. Methods are disclosedfor delivery of tools and medications into the facet joint. Methods andtechniques are disclosed to liquefy thick fluids in order to aspirateviscid material through a small tube. This is similar to developing amethod to suck oatmeal up a small soda straw. Methods and tools aredisclosed for irrigation of joints and which facilitate aspiration ofdebris and thick fluid from a facet joint. Tools and methods aredisclosed to deliver radiofrequency energy to the facet joint, nervesand/or capsule and/or to the wall of synovial cysts of the facet joint.Methods and tools are disclosed to decompress the joint fluid andtherefore a connected cyst by making an opening in the back of the facetjoint and creating an artificial posterior cyst-like cavity or reservoirfor the joint fluid on the back of the joint. Methods are disclosed forablating the synovial lining of the facet joint and cyst to reducesynovial fluid production and therefore reduce the recurrence of thecyst after either percutaneous treatment or open surgery. Methods aredisclosed for reducing scarring and adhesions around facet joints.Methods are disclosed to reduce recurrence of facet cysts aftertreatment. Methods are disclosed that may be used to drain thick fluidsthrough small tubes in other applications. Devices are disclosed thatmay be used for treating facet related back pain. Devices are disclosedthat may be used before, during or after open surgery to reduce the riskof recurrence of the synovial cyst. Devices and methods are disclosedthat may be used to ablate the synovium and capsule of joints.

Although the main focus of the disclosure is to treat spinal cystsadjacent to facet joints the disclosed subject matters and accompanyingtechniques may also be used to treat cysts around other joints (othersynovial joints). As used herein the term “cyst” includes true cysts andalso cyst-like occurrences, such as pseudocysts. Moreover, the methods,kits and tools disclosed herein may be used to treat other tissueconditions adjacent to facet joints, and in particular tissue conditionslocated to an anterior side of a facet joint. True synovial cysts arealso referred to as ganglion cysts.

One aspect of this disclosure concerns a facet joint surgical tool. Thefacet joint surgical tool may include:

a proximal portion to be disposed outside of a patient during a facetjoint surgical procedure;

a distal portion to be disposed inside a patient during a facet jointsurgical procedure;

a first rotatable member comprising a first distal end portion having afirst distal tip, with the first rotatable member being rotatable abouta first axis;

a second rotatable member comprising a second distal end portion havinga second distal tip, with the second rotatable member being rotatableabout a second axis, which second axis is different than the first axis;and

the first and second rotatable members are rotatable relative to eachother about the first axis and the second axis respectively tomanipulate the relative positioning of the first and second distal endportions between a facet joint penetration configuration (also called apiercing configuration) in which the first and second distal endportions are positioned form of piercing tip to pierce through tissueand penetrate into the facet joint and a facet joint retractionconfiguration in which the first and second distal end portions arepositioned to retract the facet joint following penetration into thefacet joint.

A number of feature refinements and additional features are applicableto this facet joint surgical tool aspect of the disclosure. Thesefeature refinements and additional features may be used individually orin any combination. As such, any of the following features may be, butare not required to be, used with any other feature or combination offeatures of this aspect or any other aspect of the disclosure.

The distal portion of one or both of the rotatable members may include abeveled end (e.g., a slanted taper). Such a beveled end, may, forexample be a beveled end of a medical needle, such as a spinal needle orhypodermic needle. Such a distal portion may be beveled at anappropriate angle for forming a piercing tip when in the facet jointpenetration configuration. The angle of the bevel, being the includedangle between a bevel face and the adjoining external wall of themember, may often be in a range having an upper limit of 25°, or 20° anda lower limit of 10° or 15°. A bevel angle in a range of from 17° to 19°may be advantageous for some implementations. One or both of therotatable members may be hollow, having a lumen, or passage,therethrough. When the rotatable members are in the facet jointpenetration configuration, the distal tips of the distal portions of themembers may be adjoining and when the rotatable members are in the facetjoint retraction configuration such distal tips may be separated by aseparation distance for refraction, or widening, of the facet joint.Such a separation distance of the distal tips may be at least 0.5millimeter, 1 millimeter, 1.5 millimeter, 2 millimeters, 2.5 millimetersor 3 millimeters. Such a separation distance may be not greater than 6.5millimeters, 5 millimeters, 4 millimeters, 3.5 millimeters or 3millimeters. When the rotatable members are in the facet jointretraction configuration, the rotatable members may each be rotated bysome amount relative to positioning in the facet joint penetrationconfiguration. Such amount may be or be approximately 180° or may be anamount that is less than or more than 180°. The respective axis of eachrotatable member may be a central longitudinal axis of that member or aportion thereof. Such longitudinal axes of the members or portionsthereof may be parallel or substantially parallel. The rotatable membersmay be in external tangential contact for at least some longitudinalportion of each rotatable member (e.g., adjoining tubes of circularcross-section in a parallel side-by-side arrangement).

Each of the rotatable members may include a longitudinally extendinginsertion portion configured for insertion into the body during asurgical operation. Such an insertion portion may have a substantiallyuniform insertion cross-section between a proximal end of the insertionportion and the distal portion of the rotatable member (e.g., a tubularinsertion portion having a uniform circular cross-section). A rotatablemember may have a total length that is longer than the insertionportion, for example a non-insertion portion that is to remain outsideof the body and which may be manipulated by a medical practitionerduring a surgical procedure. Some or all of such a non-insertion mayhave a cross-section that is the same as an insertion cross-section ofthe insertion portion. The insertion portion of a rotatable member mayhave a longitudinal length of at least 20 millimeters, 30 millimeters,40 millimeters or 50 millimeters. Such a longitudinal length may be nolarger than 200 millimeters, 150 millimeters or 100 millimeters. Theinsertion portion of a rotatable member may have a maximum crossdimension (e.g., diameter of a circular cross-section or major axis ofan elliptical cross-section) perpendicular to the respective axis ofrotation of the member, of no larger than 3.25 millimeters, 2.5millimeters, 2 millimeters, 1.75 millimeters or 1.5 millimeters. Such amaximum cross dimension may be at least 0.25 millimeter, 0.5 millimeter,0.75 millimeter, 1 millimeter, 1.25 millimeters or 1.5 millimeters. Therotatable members, or the insertion portion thereof, may be made of anysuitable material, for example stainless steel or other metallicmaterial. The rotatable members may be fabricated from hypotubes.

The insertion portion of a rotatable member may have alongitudinally-extending lumen, or passage, therethrough to provideaccess from outside of the body to the inside of the body during asurgical procedure. Such a lumen may have a maximum cross dimension(e.g., diameter of a circular cross-section or major axis of anelliptical cross-section) of at least 0.05 millimeter, 0.1 millimeter,0.25 millimeter, 0.5 millimeter, 0.75 millimeter or 1 millimeter. Such amaximum cross dimension of the lumen may be no larger than 2.5millimeters, 2 millimeters, 1.5 millimeters or 1.25 millimeters. Such alumen may have a longitudinal length of at least 10 millimeters, 20millimeters or 30 millimeters. The longitudinal length of such a lumenmay extend for at least the entire longitudinal length of the insertionportion of the rotatable member. The lumen may extend from a proximalportion of the rotatable member to the distal portion of the member. Thelumen may have a circular cross-section or may have a different shapedcross-section. The lumen may have a cross-section that is substantiallythe same over the entire length of the lumen or may have a varyingcross-section.

A lumen of one or both of the rotatable members may be fluidly connectedwith a respective fluid connection hub that is connectible with a fluidmanipulation device, such as for example a syringe, to perform a fluidmanipulation. Such a fluid manipulation may include aspiration of fluidthrough the lumen from a distal end of the lumen corresponding with adistal end portion of the rotatable member. Such a fluid manipulationmay include injecting fluid through the lumen and out of the distal endof the lumen corresponding with the distal end portion of thecorresponding rotatable member. The fluid connection hub may include aluer connector for connecting with a corresponding luer connector on thefluid manipulation device. The fluid manipulation device may include afluid containment vessel that is fluidly connected a lumen when thefluid manipulation device is connected with the fluid connection hub.The fluid containment vessel may, for example, be provided by a syringebarrel, and may contain a fluid composition for use in performing amedical procedure in the vicinity of a facet joint, for example fortreatment of a facet joint synovial cyst. Such a fluid composition maybe in the form of an aqueous irrigation liquid, for example a salinesolution. Such a fluid composition may include an active component fortreatment of a synovial cyst. Such an active component may be effectiveto liquefy or decompose (e.g., digest) tissue within a synovial cyst.Such an active component may include a hyaluronidase to liquefy tissuewithin the synovial cyst (e.g., through enzymatic activity). By“liquefy” it is meant that the viscosity of the tissue is reduced, andpreferably to an extent that it may be aspirated though a lumen of atleast one of the rotatable members. Such an active component may includea collagenase, which may be effective to decompose the tissue throughenzymatic digestion. The digested tissue may be left in the synovialcyst to be removed by normal metabolic processes. Alternatively, aftersome wait period, the digested tissue may become more liquefied and maybe aspirated for removal. A concentration of hyaluronidase orcollagenase in a fluid composition, typically an aqueous liquidcomposition, may be in any useful amount to provide some level ofliquification or tissue decomposition. Some example concentrations a forhyaluronidase are in a range of from 50 to 300 USP (United StatesPharmacopeia) units per milliliter and for a bacterial derivedcollagenase are in a range of from 0.1 to 0.5 milligrams per milliliter.Treatment of a synovial cyst to remove tissue to decompress the cyst mayinclude multiple cycles of injecting a fluid composition with such anactive agent followed by aspiration, until adequate tissue has beenremoved to affect a desired level of cyst decompression.

One or both of the rotating members may be configured to receive astylet through a lumen through the rotatable member. When the rotatablemembers are in the facet joint penetration configuration, such styletsmay be received within hollow rotatable members so that the piercing tippierces through tissue without coring that tissue, which could plugpassages through the rotatable members and interfere with subsequentprocedures that might be performed through such passages.

Such a stylet may have a beveled tip that corresponds with a beveleddistal tip of the corresponding rotatable member. The stylet may beconfigured so that when fully inserted through the rotatable member, thedistal tip of the stylet aligns with the distal tip of the rotatablemember to form a uniform penetrating tip, with the distal end of thestylet blocking the distal end of the lumen to prevent coring of tissue.

The rotatable members may include or be operatively connected withstructures or devices that are manipulable by a medical practitioner torotate the rotatable members. Such structures of devices may includehandles or levers that are hand manipulable by the medical practitionerto effect relative rotation of the rotatable members. Such structures ordevices may include an automated assembly that is actuatable toautomatically adjust repositioning of the rotatable members between thefacet joint penetration configuration and the facet joint retractionconfiguration.

The facet joint surgical tool may include a rotation actuation handleconnected with each of the rotatable members and each such rotationactuation handle may be hand manipulable to rotate the respectiverotatable member about its access of rotation to rotationally repositionthe rotatable member, for example from a facet joint penetrationconfiguration to a facet joint retraction configuration. With therotatable members conterminous at a distal end, the locations ofconnection of the rotation actuation handles may be at correspondinglongitudinal locations along the rotatable members, or may be at offsetlocations so that the handles do not come together when rotated. Such arotation actuation handle may project laterally from the rotatablemember to which it is connected to only one side of the access of therotatable members, for example to prevent interference with the adjacentrotatable member. Such rotation actuation handles may typically bedisposed proximal of an insertion portion of the rotatable member. Suchrotation actuation members may typically be disposed proximal of aproximal end of a sheath when distal portions of the rotatable membersare received through the sheath that constrains the rotatable members ina side-by-side relationship during performance of a surgical procedure.Such a rotation actuation handle may be connected to a rotatable memberdistal to a distal end of an arcuate portion when the rotatable memberincludes an arcuate portion.

One or both of the rotatable members may include a feature to enhanceutility of the rotatable members during a surgical procedure, forexample to reduce interference between proximal ends during rotation andto improve accessibility at proximal ends of the rotatable members. Insome implementations, one of both of the rotatable members may includean arcuate portion, which may alternatively be referred to as a bent orcurved portion. Such an arcuate portion may be beneficially located on anon-insertable portion of the rotatable member, for example proximal ofa rotation actuation handle. Such an arcuate portion may provide someseparation distance between proximal ends of the rotatable members toenhance accessibility and to reduce interference between the proximalends of the rotatable members during rotation. Such an arcuate portionmay preferably have a bend, or curve, that is not so sharp as to createa significant impairment to fluid flow through a lumen of the rotatablemember or insertion of a stylet or insertable surgical tools through thelumen. In some implementations, such an arcuate portion may have aradius of curvature of at least 5 centimeters, at least 10 centimetersor at least 15 centimeters. Such a radius of curvature may often be notlarger than 30 centimeters, not larger than 25 centimeters or not largerthan 20 centimeters. A rotatable member including such an arcuateportion may include a first longitudinal axis of a first longitudinalportion of the rotatable member located distal of the arcuate portionand a second longitudinal axis of a second longitudinal portion of therotatable member located proximal of the arcuate portion, and the firstlongitudinal axis and the second longitudinal axis may intersect with anacute angle of intersection between them that may be at least 3°, atleast 5°, at least 10°, at least 12° or at least 15°. Such an angle ofintersection may be not larger than 60°, not larger than 45°, not largerthan 30°, not larger than 25° or not larger than 20°. When an arcuateportion extends all of the way to a proximal end of the rotatablemember, such a second longitudinal axis may be a line tangent to thecurve of the arcuate portion at the proximal end. Such an arcuateportion may have any convenient length, and may often have a length, asmeasured along the curve of the arcuate portion, of at least 10millimeters, at least 20 millimeters, at least 30 millimeters or atleast 40 millimeters. Such a length of the arcuate portion may often benot larger than 150 millimeters, not larger than 100 millimeters, notlarger than 75 millimeters, or not larger than 60 millimeters. A distalend of the arcuate portion may be located a significant distance fromthe distal tip of the rotatable members. Such a distance from the distaltip may be at least 20 millimeters, at least 40 millimeters, at least 60millimeters, or at least 80 millimeters. Such a distance may often benot more than 250 millimeters, not more than 200 millimeters or not morethan 150 millimeters.

The facet joint surgical tool may include a sheath having an internalpassage through which the rotatable members are disposed with at leastthe distal tips of the members being disposed or able to be disposeddistal to a distal end of the sheath. The internal passage may have aminimum area cross-section through which the rotatable members aredisposed, and such a minimum area cross-section may have an aspect ratioof at least 1.25:1, 1.5:1 or 1.75:1. The aspect ratio may be no largerthan 3:1, 2.5:1 or 2.25:1. An aspect ratio of an area (e.g. minimumcross-section) refers to a ratio of the maximum cross dimension of thearea (length dimension of the area) to a width dimension that is amaximum cross dimension of the area perpendicular to the lengthdimension (e.g., for an ellipse a ratio of the major axis to the minoraxis). The minimum area cross-section may have an oval shape. Such aminimum area cross-section may have a maximum cross dimension (e.g.,major axis of an elliptical cross-section) of at least 0.5 millimeter, 1millimeter, 1.5 millimeters, 2 millimeters, 2.5 millimeters or 3millimeters. Such a maximum cross dimension may be no larger than 6.5millimeters, 5 millimeters, 4 millimeters, 3.5 millimeters or 3millimeters. The minimum area cross-section may be configured tomaintain, or constrain, the rotatable members in a side-by-sideorientation through the minimum cross-section, or even through theentire internal passage of the sheath. In such a side-by-sideorientation the rotatable members may be translatable through theminimum area cross-section of the sheath in a longitudinal directionthrough the internal passage but may be substantially not translatablewithin the minimum area cross-section in a lateral direction,perpendicular to such longitudinal direction. When such rotatablemembers are in such a side-by-side orientation, a clearance fit betweenthe rotatable members and the sheath may be no larger than 0.5millimeter, 0.3 millimeter, 0.2 millimeter or 0.1 millimeter. By aclearance fit of a structure or structures received in a receivingstructure, it is meant that the received structure or structures (e.g.,the rotatable members) as properly received (e.g., in the sheath) maymove laterally within the receiving structure perpendicular to adirection of insertion of the received structure or structures into thereceiving structure by no more than that amount. The internal passage ofthe sheath may have a cross-section that is equal to the minimum areacross-section for at least 1 millimeter, 5 millimeters, 10 millimetersor 20 millimeters along the length of the internal passage. The internalpassage of the sheath may have a cross-section that is equal to theminimum area cross-section for substantially the entire length of theinternal passage. The rotatable members as disposed through the sheathmay be such that their respective longitudinal axes do not cross orintersect within the internal passage. Such axis may be parallel throughthe internal passage of the sheath.

The sheath may have a longitudinally extending insertion portion forinsertion into a patient's body during a surgical operation. Theinsertion portion of the sheath may have a longitudinal length of 10millimeters, 20 millimeters or 30 millimeters. Such an insertion portionof the sheath may have a longitudinal length of no greater than 200millimeters, no greater than 150 millimeters or no greater than 100millimeters. The insertion portion of the sheath may have an insertioncross-section with an aspect ratio as described previously for theminimum cross-section of the internal passage of the sheath. Forexample, the insertion cross-section may have an aspect ratio of atleast 1.25:1, 1.5:1 or 1.75:1. The insertion cross-section may have anaspect ratio of no larger than 3:1, no larger than 2.5:1 or no largerthan 2.25:1. The insertion cross-section of the sheath may have amaximum cross dimension (e.g., diameter for a circular cross-section,major axis for an elliptical cross-section) of no larger than 8millimeters, 6 millimeters, 5 millimeters, 4.5 millimeters, 4millimeters or 3.5 millimeters. Such a maximum cross dimension may be atleast 0.7 millimeter, 1.25 millimeters, 1.75 millimeters, 2.25millimeters, 2.75 millimeters, 3.25 millimeters or 3.5 millimeters. Theinsertion cross-section of an insertable structure (e.g., the sheath)identifies a minimum area perpendicular to a direction of insertionthrough which the insertable structure is able to pass during insertion.The insertion portion of the sheath may have an insertion cross-sectionthat has an oval shape, for example corresponding with an oval shape ofthe internal passage through the sheath. The sheath may have asubstantially uniform cross-section over the entire length of theinsertion portion of the sheath (e.g., a uniform oval cross-section).The sheath may have a non-insertion portion that is to remain outside ofa patient's body during use, and through which the rotatable members areinsertable for insertion into the body. The non-insertion portion of thesheath may have a cross-section that is the same as a cross-section ofthe insertion portion of the sheath.

The sheath may advantageously have a tapered distal end portion, whereinan exterior cross-section of the sheath tapers to a smaller size movingtoward the distal end of the sheath. Such a tapered distal end portionof the sheath facilitates clean penetration of tissue when the facetjoint surgical tool is configured to pierce through tissue to access afacet joint. The exterior cross-section taper may be accomplishedthrough gradually reducing the wall thickness of the sheath on thedistal end portion of the sheath, for example by grinding off a portionof the wall thickness from a portion of the sheath adjacent the distalend. In preferred implementations, an internal passage through thesheath does not taper to a smaller size in the tapered distal endportion of the sheath. Such a tapered distal end portion may extend fromthe distal end of the sheath to a location that may be at least 1millimeter, at least 1.5 millimeters, at least 2 millimeters or at least2.5 millimeters. Such a tapered distal end portion of the sheath maybegin at a location not more than 10 millimeters, not more than 7millimeters, not more than 5 millimeters, not more than 4 millimeters ornot more than 3 millimeters from the distal end of the sheath.

The sheath may have walls made of an electrically conductive material,such as a metallic material (e.g., stainless steel) when one or morecomponents of the facet joint surgical tool is to be used to transmitradio frequency (RF) energy for performing a RF ablation procedure toablate tissue during a surgical operation, the sheath may include anelectrically insulating coating or covering over the exterior surface ofsome or all of the sheath, to prevent RF energy from being transmittedlaterally to tissue not targeted for ablation. Such an electricallyinsulating covering may be of a plastic, or polymeric, composition, forexample including a polyolefin material (e.g., polyethylene,polypropylene, ethylene-propylene copolymers).

When the facet joint surgical tool is to be used to perform a RFablation procedure using one or more components of the facet jointsurgical tool to transmit the RF energy to the tissue to be ablated, theRF energy may be transmitted through one or both of the rotatablemembers or through the sheath. A RF signal generator may be connected,for example, with one or both of the rotatable members. The connectionmay be made at a proximal location that is proximal of the sheath whendistal portions of the rotatable members are disposed through the sheathduring a surgical procedure.

The facet joint surgical tool of this aspect may be or have features ofa rotatable blade access device (Rbad) as described below in theDetailed Description section, or may otherwise have features disclosedin the Detailed Description section.

Another aspect of this disclosure concerns a kit that is useful inperformance of a medical procedure in the vicinity of a facet joint. Thekit includes at least components assembled or assemblable into a facetjoint surgical tool, or a subassembly of such a facet joint surgicaltool, such as for example according to the facet joint surgical toolaspect of the disclosure. In that regard, the kit may include a firstrotatable member, a second rotatable member and a sheath, which asprovided in the kit may be either assembled or assemblable into thefacet joint surgical tool, or subassembly thereof, of the facet jointsurgical tool aspect of the disclosure.

A number of feature refinements and additional features are applicableto this kit aspect of the disclosure. These feature refinements andadditional features may be used individually or in any combination. Assuch, each of the following features may be, but are not required to be,used with any other feature or combinations of features of this kitaspect or any other aspect of the disclosure.

A first rotatable member, second rotatable member and sheath of the kitmay be or have any feature or combination of features described withrespect to the facet joint surgical tool of the facet joint surgicaltool aspect of this disclosure.

The kit may include one or more other components in addition to therotatable members and the sheath. The kit may include any component orcomponents described in relation to the facet joint surgical tool aspectof the disclosure.

The kit may include at least one fluid composition for use in performinga medical procedure in the vicinity of a facet joint using one or morecomponents of a facet joint surgical tool of the kit. As used herein, inthe vicinity of the facet joint refers to in the facet joint or near thefacet joint. Such a fluid composition may comprise an irrigation liquid.Such a fluid composition may comprise a drug (active component) fortreating a condition in the vicinity of the facet joint, for example totreat for a synovial cyst. Such a fluid composition may include ahyaluronidase. Such a fluid composition may include a collagenase. Sucha fluid composition may be provided in a fluid container. Such a fluidcomposition may be provided in a syringe prefilled with the fluidcomposition. Such a fluid composition may be irrigation liquid. Such afluid composition may be or have any feature of features as describedwith respect to the facet joint surgical tool aspect of the disclosure.The kit may include multiple fluid compositions for different uses(e.g., irrigation liquid and active component formulation), and the kitmay include multiple fluid containers (e.g., multiple pre-filledsyringes) containing different fluid compositions. The kit may includemultiple fluid containers (e.g., multiple pre-filled syringes) that eachcontain the same fluid composition, such as may be useful for performinga procedure multiple times using different volumes of the fluidcomposition (e.g., multiple treatments with hyaluronidase orcollagenase).

Yet another aspect of this disclosure concerns a method for performing amedical procedure in the vicinity of the facet joint, and such a methodmay include using a facet joint surgical tool, such as according to thefacet joint surgical tool aspect of the disclosure or as may be providedby the kit aspect of the disclosure.

A number of feature refinements and additional features are applicableto this method aspect. These feature refinements and additional featuresmay be used individually or in any combination. As such, each of thefollowing features may be, but are not required to be, used with anyother feature or combination of features of this method aspect or otheraspects of this disclosure.

The facet joint surgical tool may be used to treat facet joint synovialcysts, including such cysts located to an anterior side of facet jointsand, such cysts located to a posterior side of facet joints. The facetjoint surgical tool will typically be inserted through tissue of apatient to access the vicinity of a facet joint from a posterior side ofthe facet joint. The piercing and retraction features of the facet jointsurgical tool may be used to enter and retract a facet joint to provideaccess through the facet joint for treatment of a synovial cyst locatedto an anterior side of the facet joint. The facet joint surgical toolmay be used to directly access a synovial cyst located to the posteriorside of a facet joint, for example to pierce through tissue to thesynovial cyst and to pierce into the synovial cyst to perform a medicalprocedure in relation to the posterior synovial cyst.

A method for treating a tissue condition in or anterior to a facet jointmay include accessing and retracting the facet joint from a posteriorside opposite the synovial cyst; and with the facet joint retracted,performing a medical procedure from the posterior side through theretracted facet joint to treat tissue in or anterior to the facet joint.The tissue condition may be a synovial cyst, which may be anterior tothe facet joint. The medical procedure may include any proceduredescribed with respect to the facet joint surgical tool aspect of thedisclosure or the kit aspect of the disclosure. The medical proceduremay include applying suction to the facet joint or directly to asynovial cyst or other tissue for aspiration of fluid. The medicalprocedure may include injecting a fluid composition into the facet jointto apply fluid pressure to a synovial cyst or other tissue. Sufficientpressure may be applied to rupture a synovial cyst or to increase thefluid communication between the facet joint and a synovial cyst. Themedical procedure may include injecting a fluid composition into thefacet joint or directly into a synovial cyst wherein the fluidcomposition comprises at least one component to liquefy or decomposetissue within the synovial cyst. Such a component may be an activecomponent such as a hyaluronidase or a collagenase. After injecting afluid composition, a medical procedure may include removing liquid fromthe facet joint, for example to also draw fluid from a synovial cyst, orto remove liquid directly from a synovial cyst, for example by insertinga fluid suction tool through the sheath and through the facet joint todirectly penetrate into the volume of an anterior synovial cyst.Removing liquid from the facet joint or directly from a synovial cystmay be performed after a wait time to permit the hyaluronidase orcollagenase to reduce the viscosity of tissue within the synovial cystto facilitate enhanced aspiration. Such a wait time may be on the orderof minutes or hours. In some implementations, such a wait time may be atleast 5 minutes, at least 20 minutes or at least 30 minutes. In someimplementations such a wait time may be less than 4 hours, less than 3hours, less than 2 hours or less than 1 hour. In some implementations,the wait time may be for a more extended time, for example overnight oreven a few days, with aspiration to remove liquefied synovial cystmaterial occurring on a later day than the day on which the fluidcomposition containing the active agent is provided to a synovial cyst.A medical procedure may include irrigating through the facet joint ordirectly irrigating a synovial cyst, which may assist in removingliquefied material from the synovial cyst. The medical procedure mayinclude a tissue ablation procedure, for example RF ablation,cryoablation or ultrasound ablation. Such a tissue ablation proceduremay be performed by transmitting an ablation tool through the sheath andthrough the facet joint to directly access the volume of a synovialcyst.

Following one or more such medical procedures, a tissue ablationprocedure may be performed to ablate at least a portion of the synoviumat the posterior side of the facet joint. Such tissue ablation mayinclude RF ablation, cryoablation, ultrasound ablation or chemicalablation. In some implementations, such tissue ablation may be performedby RF ablation using one or more components of a facet joint surgicaltool of the facet joint surgical tool aspect to transmit the RF energyto a distal area of the facet joint surgical tool, as describedelsewhere in this disclosure. Such a tissue ablation procedure may forman artificial cavity in or adjacent to the posterior side of the facetjoint to provide a volume to receive synovial fluid as an alternative topressurizing an anterior side of the facet joint, which may result inrecurrence of an anterior synovial cyst. Such an artificial cavity mayprovide an open volume to relieve pressure from the anterior side of thefacet joint. The method may include a first tissue ablation procedure atthe posterior side of a facet joint to prepare such an artificialcavity. After such first tissue ablation procedure, the method mayinclude a second tissue ablation procedure to the posterior side of thefacet joint at a location posterior of the location of the first tissueablation procedure. The second tissue ablation procedure may be directedto destroying at least a portion of the synovium on the posterior sideprior to termination of the surgical procedure.

The method may include use of a facet joint surgical tool of the facetjoint surgical tool aspect to perform some portion of the method. Themethod may include, prior to the retracting the facet joint, penetratinginto tissue of a patient with a distal piercing tip of a facet jointsurgical tool, such as of the facet joint surgical tool aspect. Aftersuch penetrating, a piercing tip of a facet joint surgical tool may beadvanced through tissue of the patient to the posterior side of thefacet joint and the facet joint may be retracted by rotating rotatablemembers of the facet joint surgical tool to reposition distal tips ofthe rotatable members from a facet joint penetration configuration to afacet joint refraction configuration. Stylets may be disposed throughlumens through the rotatable members during the penetrating. Suchstylets may be removed before or after reconfiguring the facet jointsurgical tool for refraction of the facet joint. The method may include,after retracting the facet joint with distal tips of the rotatablemembers, advancing the sheath of a facet joint surgical tool into thefacet joint to a depth to effect retraction of the facet joint with thesheath, permitting the rotatable members to be used for performing amedical procedure or permitting such rotatable members to be removedfrom the sheath to provide an access route for inserting other tools tothe vicinity of the facet joint for use in a medical procedure. Avariety of insertable tools may be advanced through the sheath into thepatient for use and performing a medical procedure. Such insertablesurgical tools may include fluid injection and/or aspiration tools,wires or flexible needles for accessing and puncturing the anteriorsynovial cyst, and ablation tools. Alternatively, one or more suchinsertable tools, for example catheter-type tools, may be insertedthrough a lumen of rotatable member while the rotatable member is stilldisposed through the sheath.

The method may include penetrating into a facet joint capsule of a facetjoint using the facet joint surgical tool with rotating memberspositioned in a facet joint penetration configuration. The penetratingmay comprise advancing at least distal tips of the rotating members intothe facet joint capsule. After penetrating into the facet joint capsule,the method may include rotating the rotatable members to reconfigure therotating members to a facet joint retraction configuration. With therotatable members in such a facet joint retraction configuration, thefacet joint may be refracted, or widened, in a manner to permit avariety of medical procedures to be performed in the vicinity of thefacet joint, for example in or through the facet joint, for example oneor more medical procedures as described above. After reconfiguring therotatable members to the facet joint retraction configuration, thesheath may be advanced from outside to inside of the facet jointcapsule, and the sheath may maintain the facet joint in a retractedposition. After the penetration into the facet joint capsule, a fluidcomposition may be conducted through a lumen of at least one of therotating members to exit the lumen in the vicinity of the facet joint.Fluid may also be aspirated from the vicinity of the facet joint throughthe lumen of the other rotating member, such as may be appropriate foran irrigation procedure. A medical device may be conducted through thelumen of one of the rotating members to the vicinity of the facet joint,and a medical operation may be performed in the vicinity of the facetjoint using the medical device. Such a medical device may be a surgicaldevice. At least one of the distal portions of the rotating members maybe a RF electrode and the method may include operating the RF electrodeto perform a RF ablation procedure on tissue in the vicinity of thefacet joint.

In another aspect of the disclosure, a method may include treating afacet joint synovial cyst, whether located on a posterior side of thefacet joint or an anterior side of the facet joint, with a methodincluding introducing into tissue of the synovial cyst a fluidcomposition including at least one active component, or active agent, todecompose or liquefy tissue within the synovial cyst. When treating afacet joint synovial cyst located on an anterior side of the facetjoint, access to the synovial cyst may be as described with respect tothe method aspect above for treating a synovial cyst on an anterior sideof a facet joint. When treating a synovial cyst located on a posteriorside of the facet joint, the synovial cyst may be directly accessed fromthe posterior side of the patient using minimally invasive surgicaltools to penetrate tissue and advance to a depth of the synovial cyst.Such treatment of a posterior synovial cyst may be performed using thefacet joint surgical tool of the facet joint surgical tool aspect, eventhough access to the synovial cyst does not require providing accessthrough the facet joint. The posterior synovial cyst may be pierceddirectly with a piercing tip of the facet joint surgical tool. Needletips of the rotatable members may be rotated to cut tissue within thesynovial cyst. The fluid composition may be introduced directly into thesynovial cyst from lumens through the rotatable member. Tissue of thesynovial cyst may be ablated using an insertable ablation tool insertedthrough a lumen of a rotatable member or through the sheath with therotatable members removed. Alternatively, tissue ablation may beperformed using one or more components of the facet joint surgical toolto transmit the RF energy to the tissue to be ablated. The method mayinclude, after treating the synovial cyst, performing one or more tissueablations, for example to destroy at least a portion of the synovium onthe posterior side of the facet joint, as described elsewhere.

Further aspects of the disclosure include the use of a hyaluronidase orother collagenase for treatment of a facet joint synovial cyst, whichmay be located posterior of a facet joint or anterior of a facet joint.

These and other aspects of the disclosure, and other additional featuresand feature refinements applicable to these and other aspects of thedisclosure, will be apparent with reference to the following DetailedDescription, the drawings and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates generally facet joints.

FIG. 2 illustrates a facet joint with a synovial cyst located anteriorto the facet joint.

FIG. 3 illustrates rotatable members useful for a facet joint surgicaltool.

FIG. 4 illustrates the rotatable members of FIG. 3 oriented in a facetjoint penetration configuration with a piercing tip.

FIG. 5 illustrates the rotatable members of FIG. 4 being reconfiguredfrom a facet joint penetration configuration to a facet joint retractionconfiguration.

FIG. 6 illustrates a facet joint surgical tool with rotatable membersdisposed through a sheath and configured with a piercing tip penetratinginto a facet joint from a posterior side.

FIG. 7 illustrates the facet joint surgical tool of FIG. 6 withrotatable members reconfigured to retract a facet joint.

FIG. 8 illustrates the sheath of the facet joint surgical tool of FIGS.6 and 7 after advancement of the sheath to retract the facet joint andremoval of the rotatable members from the sheath.

FIG. 9 illustrates rotation of the sheath of FIG. 8 to adjust retractionof a facet joint with the sheath.

FIG. 10 illustrates passage of a surgical tool through the sheath of thefacet joint surgical tool of FIGS. 6 and 7 with the rotatable membersremoved.

FIG. 11 illustrates circulation of liquid, such as irrigation liquid,using lumens of rotatable members.

FIGS. 12-15 illustrate a kit and components thereof.

FIGS. 16 and 17 illustrate an assembled facet joint surgical tool usingcomponents of the kit of FIGS. 12-15 with rotatable members configuredin a facet joint penetration configuration and facet joint retractionconfiguration, respectively.

FIG. 18 illustrates another kit and components thereof.

FIG. 19 illustrates an assembled facet joint surgical tool usingcomponents of the kit of FIG. 18.

FIGS. 20-28 illustrate use of a facet joint surgical tool to treat froma posterior side a synovial cyst located anterior of a facet joint.

FIG. 29 illustrates use of a rotatable member of a facet joint surgicaltool as a RF electrode for performance of a RF tissue ablationprocedure.

DETAILED DESCRIPTION

For a more complete understanding of the invention and aspects thereof,reference is now made to the following Detailed Description taken inconjunction with the figures.

In one embodiment, an access device is formed by two elongated roundhollow metal tubes of circular cross-section. The ends of the tubes maybe cut at an angle. The tube edges may be sharpened, such as a pointedtip of a spinal needle or hypodermic needle. The two tubes may beinserted through and constrained by a smooth outer sheath. Thus theouter sheath may be oval shaped in cross section and rigid. The rigidsheath may prevent the tubes from crossing or overlapping duringinsertion or rotation of the tubes. The sheath may be sized to allow thetubes to freely rotate. Before the access device is inserted into theskin and deep tissues, the angled ends of the tubes may first be rotatedto face in opposite directions. The two sharpened edges may now form asingle blade-like surface. For convenience such a device may be referredto as a rotatable blade access device (“Rbad” for short). The sharpenedtip of the Rbad acting like a single needle allows the two tubes topierce the skin and tissues and be placed smoothly into the desiredlocation. The tip of the Rbad is placed in the facet joint. In onemethod the device Rbad is placed with the blade edges parallel to thefacet joint surface. After the Rbad tip is placed in the facet jointthen the two tubes are each rotated 180 degrees. The blade tips are nowseparated forcing the two articular surfaces of the facet joint apartcreating a retracted working space for instruments or medications andalso forming a slit in the joint capsule. The maximum distance the tipsof the tubes may be separated, and therefore the two surfaces of thefacet joints separated, is equal to the sum of the outer diameters ofthe tubes. If desired the tubes may be rotated separately or inincrements. Therefore the facet joint may be widened gradually rangingfrom the minimal width of the thin tip of the Rbad before rotation tothe maximal width equal to the sum of the outer diameters of the twotubes. In one embodiment the outer sheath is made of metal and is rigidand formed from a material such as stainless steel. The metal ovalsheath may then be wedged into the joint, and the sheath may then serveas a portal allowing for passage of other larger instruments into thejoint during treatment. After a cyst is treated the sheath may then berotated 90 degrees, so that the long axis of the oval shaped crosssection of the sheath is now parallel to the joint surfaces to allow foreasy removal of the sheath from the facet joint.

In one embodiment of a method, the blade-like dual lumen tip of the Rbadis placed perpendicular to the facet surface. The blades may then berotated and thus opened to incise a slit in the facet capsule parallelto the surfaces of the facet joint. Then the oval outer sheath may bepushed, wedged or hammered into the joint. Then the oval shaped sheathmay be rotated 90 degrees to widen the facet joint opening.

In some patients joints may be severely arthritic. Bony osteophytes orspurs may bridge and therefore obstruct access to the joint. In thesepatients the same oval access sheath trocar may be used. The Rbad isplaced against the back of the facets and then the rotatable tubes arerotated rapidly to drill and remove the bone over the back of the facet.Alternatively, instead of using the Rbad two drill bits of similardiameter to the tubes may be used to remove the bone covering the backof the narrow joints. Then in either case the Rbad may be positioned toretract the joint or the oval access sheath may be wedged and rotated towiden the joint.

All these methods and devices allow access to the now widened facetjoint. Then if desired, another instrument such as, for example aradiofrequency ablation electrode, coaxial trocar or endoscopy, may bepassed either into the retracted open joint or navigated into or near tothe facet capsule or synovial cyst.

If RF ablation is used in another embodiment, the outer sheath may bemade of plastic or other electrically insulating material. Alternativelythe Rbad, except for a distal portion, may covered with an insulatingmaterial and the tip may then be used as a RF ablation device.

In another embodiment of a method, the joint is accessed with the Rbadand the joint directly aspirated. Synovial cysts communicate with theadjacent joint and therefore the synovial cyst may be aspiratedindirectly when the joint is aspirated. If the fluid is too thick toaspirate, then a hyaluronidase may be injected. The dual tube designallows for easy injection of hyaluronidase or other treatmentcomposition into the joint. The retractor opens the joint and widens thecommunication between the cyst and joint and allows the medication(e.g., hyaluronidase) to more easily flow into the cyst. Hyaluronidasesare enzymes that are used for digesting proteins. This has been usedclinically to reduce scar formation in the cornea and also to removeexcess collagen from cosmetic procedures. Also collagenases have beenused clinically to reduce and dissolve scar tissue in peronie's diseaseand dupuytren's contracture. A collagenase safely digests the collagenin scar tissue Hyaluronidase safely digests proteins liquifying theviscid synovial fluid in the joint and cyst. This facilitates aspiratingthe very thick, gel-like synovial fluid within the cyst through thesmall tubes of an Rbad or, if desired, through the outer oval sheath.

The wall of a synovial cyst is typically thinner and weaker than thecapsule of the adjacent joint. In another embodiment of a method afluid, such as for example saline, is injected through the Rbad todistend and pressurize the capsule and communicating cyst until there isa sudden loss of resistance in the system indicating cyst rupture. Thepressure on the spinal canal is then relieved. Myelogram contrast mediamay be injected into the joint to visualize the cyst and joint capsule.A successful endpoint of such a treatment may be visualization ofcontrast in the epidural space of the spinal canal. This procedure maybe referred to as a trans-facet epidurography. The trans-facetepidurogram can be imaged with either CT, fluoroscopy or MRI. In anotherembodiment, after the cyst is ruptured a hyaluronidase and/or acollagenase is injected through the facet into the epidural space toreduce adhesions, scarring and recurrence of the cyst.

It is observed that anterior cysts are rarely seen associated withposterior located cysts. The anterior cysts are usually symptomaticbecause the nerves and sensitive tissues are located in front of thejoint. A further use of the device is to create an artificial cyst alongthe back of the joint to reduce the pressure in the anterior joint andhelp prevent recurrence. In one embodiment of a method, after treatmentthe Rbad is positioned on the back of the facet capsule and the bladesare rotated either in the same direction or in opposite directionsrapidly creating a cavity. Fluid is injected through one lumen andaspirated by vacuum through the other lumen. In another embodiment of amethod the Rbad is positioned just within or posterior to the joint anda radiofrequency lesion is performed ablating the posterior capsule andsynovium and creating an artificial cyst-like cavity. One or morelesions may be created. The artificial cysts act as reservoirs thusdecreasing the pressure in the joint and anterior capsule reducing therisk of recurrence of the symptomatic anterior cyst. If desired,surgery, focused ultrasound, coblation techniques or laser energy may beused to create such an artificial posterior cyst cavity.

In a further embodiment, the Rbad dual tubes may function as either aunipolar or bipolar RF electrode, and the tubes may be either slowly orrapidly rotated. This may provide an improvement relative to stationaryRF electrodes as rotating electrodes distribute the RF energy moreuniformly. Also certain trajectories of motion distribute energy moreuniformly and efficiently than others.

In another embodiment of a method, the cyst is directly accessed andtreated with the Rbad with a or coaxial tube or insulated wire insertedthrough a tube or sheath of the Rbad.

In another embodiment of a method, the neck of a cyst may be accessed bya Rbad or coaxial tube or insulated wire inserted through a tube ofsheath of the Rbad. The cyst is first aspirated and/or ruptured and thenthe neck of the cyst is ablated preventing recurrence. The neck of thecyst may be treated for example with RF ablation or cryoablation toocclude the channel between the cyst and joint.

The synovium of the joint produces the fluid filling the joint anddistending the cyst. In one preferred embodiment, the cyst wall andfacet capsule may be ablated with RF energy. This embodiment isspecifically directed at synovial ablation. Conductive fluid such assaline may be circulated through the system increasing the effectivesize of the Rbad electrode allowing for ablation of more synovium. Thispartially ablates the synovium, reducing the production of synovialfluid and reducing the risk of recurrence of the cyst. This also treatspain by reducing capsular distension and treating posterior capsularstructures. In variations of this embodiment the Rbad may be used eitheras the primary method of percutaneous treatment or prior to, after orduring an open surgical procedure to reduce the risk of recurrentsynovial cysts of the facet joints after surgery.

Since there are two tubes, which may be in the form of needles (e.g.,spinal needles or hypodermic needles), forming the tip of the Rbaddevice, fluid may be circulated in the system by injecting or pumpingfluid through one tube and aspirating fluid by suction or vacuum throughthe other tube. This allows the operator to remove debris, small bone orcartilage fragments and blood by circulating fluid thus flushing andcleaning both the joint and cyst.

The Rbad is a multipurpose device that may function as a tissueresector, trocar, drill, access device, retractor, irrigator and/or RFablation electrode.

FIG. 1 illustrates a portion of a vertebral column showing the generallocation of facet joints 102 between superior and inferior processes ofthe vertebrae. FIG. 2 is an illustration of a portion of a vertebralcolumn as shown in FIG. 1, but showing a synovial cyst 104 locatedanterior to a facet joint 102. FIG. 3 is an illustration of tworotatable hollow members 106 (e.g., tubes, needles) with pointed distalportions 108 that may be used as rotatable members, or tubes, of anRbad. FIG. 4 shows the same two hollow members 106 as shown in FIG. 3 inadjacent relation as they may be constrained within a sheath of a Rbadand with the hollow members 106 rotated to relative positions where thedistal portions 108 are in a facet joint penetration configuration withdistal portions positioned to form a piercing tip to pierce throughtissue and penetrate into a facet joint. In a preferred facet jointpenetration configuration the hollow members are adjoining, with no oressentially no gap between them as constrained within a sheath. FIG. 5is an illustration of the same hollow members 106 as shown in FIGS. 3and 4 and showing rotation of the hollow members 106 about theirrespective longitudinal axes to change the positioning of the distalportions 108 between a facet joint penetration configuration 110 and afacet joint refraction configuration 112. Arrows in FIG. 5 show anexample of relative rotation of the hollow members 106 to change fromthe facet joint penetration configuration 110 to the facet jointretraction configuration 112.

FIG. 6 is an illustration showing a facet joint surgical tool 120 (e.g.,a Rbad) with two rotatable hollow members 122 disposed through a sheath124 and positioned in a facet joint penetration configuration with atissue piercing tip that has penetrated into the facet joint 102. FIG. 7shows the same surgical tool 120 with the hollow members 122 rotated toposition the pointed distal portions of the hollow members in a facetjoint retraction configuration to widen the facet joint 102 followingpenetration into the facet joint 102. FIG. 8 shows the sheath 124 of thesame surgical tool 120 after the sheath 124 has been advanced into thefacet joint to maintain retraction of the facet joint. As shown in FIG.8, the hollow members 122 have been removed from the sheath 124,permitting the sheath 124 to be used as a conduit for conduction othermedical tools or fluid compositions into or through the retracted facetjoint 102. The arrow in FIG. 8 shows that the sheath 124, which has anoval cross section, may be rotated between retracting and non-retractingpositions, which are illustrated in FIG. 9. In a retracting position,the major, or long, axis of the oval cross-section of the sheath 124 isperpendicular to the facets of the facet joint, and the ends of thesheath 124 at opposite ends of the long axis of the oval cross-sectionpush against the facets and wedge the facet joint into a retracted, orwidened position. In a non-retracting position, the minor, or short,axis of the oval-cross section of the sheath 124 is perpendicular to thefacets and the facet joint 102 is in an unretracted or less retractedsituation. The non-retracting position of the sheath may be beneficial,for example, to permit easier withdrawal of the sheath 124 from thefacet joint 102, for example at the conclusion of a surgical procedure.FIG. 10 shows the sheath 124 used as a conduit to conduct a medical tool126 (e.g., a wire) to the facet joint 102 and through the facet joint102 to the vicinity of the cyst 104, for example to perform a surgicaloperation on or in the vicinity of the cyst 104 (e.g., to puncture thecyst).

FIG. 11 shows adjacent rotatable hollow members 130 with pointed distalend portions positioned in a facet joint retraction configuration, andwith arrows showing a possible fluid circulation path with fluid beingdelivered from one hollow member 130 b and aspirated through the otherhollow member 130 a. Such fluid circulation may, for example, be used toirrigate in the vicinity of a facet joint.

Reference is now made FIGS. 12-17 illustrating one example embodiment ofa kit with components useful for performance of a medical procedure inthe vicinity of a facet joint, for example to treat a synovial cyst.Shown in FIG. 12 is an example kit 150 with components assemblable intofacet joint surgical tool configurations. The kit 150 include first andsecond rotatable working pieces 152 a,b, each having a distal end 154a,b and a proximal end 156 a,b and with a rotatable member 158 a,b,fluid connection hub 160 a,b and rotation actuation handle 162 a,b. Therotatable members 158 a,b include insertion portions 164 a,b disposeddistal of the corresponding rotation actuation handle 162 a,b andnon-insertion proximal portions including connection locations for therotation actuation handles. As shown in FIGS. 13C and 14C, the rotatablemembers 158 a,b include distal portions 166 a,b that taper toward thedistal tips 154 a,b. The rotatable member 158 a of the working piece 152a includes an arcuate portion 168 with a bend that helps to keep thefluid connection hubs 160 a and 160 b from interfering when therotatable members 158 a and 158 b are rotated relative to one another.The bend of the arcuate portion 148 also makes it easier to connect thefluid hubs 160 a, 160 b with fluid manipulation devices (e.g., syringes)without the fluid manipulation devices interfering with each other.

The kit 150 includes a sheath 174 including a distal end 176 and aproximal end 178. The sheath 174 includes an internal passagetherethrough sized to receive and constrain in a side-by-siderelationship the insertion portions 164 a and 164 b of the rotatablemembers 158 a,b. The sheath 174 includes a tapered distal end portion182 adjacent the distal end 176 of the sheath 174. In the tapered distalend portion 182, the exterior cross-section of the sheath 174 reduces insize toward the distal end 176 as the thickness of the sheath wall isreduced toward the distal end 176 along the tapered distal end portion182. The cross-section of the internal passage 180 is constant throughthe entire length of the sheath 174. The sheath 174 includes a maximumexterior cross-section, as best shown in FIG. 15C, that includes alarger first cross dimension OD1 than the second cross dimension OD2. Sothat the maximum exterior cross-section of the sheath 174, and thereforealso the insertion cross-section of the sheath 174, has an aspect ratio(OD1/OD2) of larger than one. Likewise, the minimum area cross-sectionwithin the internal passage 180 includes a first cross dimension ID1that is larger than the second cross dimension ID2 and therefore alsohas an aspect ratio (ID1/ID2) of greater than one.

The kit 150 also includes two stylets 190 a,b including solid needleinsert members 192 a,b extending from hand-manipulable heads 194 a,b.The stylets 190 a,b include pointed distal tips 196 a,b. The stylets 190a,b are configured for insertion of the needle insert members 192 a,bthrough the working pieces 152 a,b with the distal tips 196 a,bcorresponding with the distal ends of lumens through the rotatablemembers 158 a,b adjacent the distal tips 154 a,b, to block the distalends of the lumens to prevent tissue coring when the rotatable members158 a,b are positioned in a piercing configuration and used to piercethrough tissue during a surgical procedure. The fluid connection hubs160 a,b and the heads 194 a,b of the stylets 190 a,b may havecorresponding keyed features that properly align beveled stylet ends atthe distal tips 196 a,b with beveled needle points of the distal endportions 166 a,b or the rotatable members 158 a,b when the insertionneedle members 192 a,b are fully inserted through the rotatable workingpieces 152 a,b with the heads 194 a,b engaged with the fluid connectionhubs 160 a,b.

FIGS. 16 and 17 illustrate an example facet joint surgical tool 200including an assembly of the working pieces 152 a,b, sheath 174 andstylets 190 a,b of the kit 150. In the assembly of the facet jointsurgical tool 200, the insertion portions of the rotatable members 158a,b are disposed through the internal passage of the sheath 174 with thedistal tips 154 a,b disposed distal of the distal end 176 of the sheath174. The rotation actuation handles 162 a,b are disposed proximal of theproximal end 178 of the sheath 174. The needle insert members 192 a,b(not shown in FIGS. 16 and 17) are inserted through the working pieces152 a,b with the heads 194 a,b engaged with the fluid connection hubs160 a,b of the working pieces 152 a,b. FIG. 16 shows the facet jointsurgical tool 200 with the rotatable members 158 a,b rotated to relativepositions where the distal end portions 166 a,b are in a facet jointpenetration configuration with a piercing tip to pierce though tissueand penetrate into a facet joint as needed for a facet joint surgicalprocedure. FIG. 17 shows the rotatable members 158 a,b rotated torelative positions with the distal end portions 166 a,b in a facet jointretraction configuration with the distal tips 154 a,b separated byapproximately the combined diameters of the rotatable members 158 a,b.As shown in FIG. 17, in the facet joint retraction configuration therotatable members 158 a,b have each been rotated 180° relative topositioning shown in FIG. 16 through manipulation of the rotationactuation handles 162 a,b, as shown by the rotational arrows in FIG. 17.In either of the configurations shown in FIGS. 16 and 17, the stylets190 a,b may be removed from one or both of the working pieces 152 a,b toopen the lumen through the respective rotatable member 158 a,b to permitaccess for medical procedures during a surgical operation.

Referring now to FIG. 18, another example kit 210 is shown that includesthe working pieces 152 a,b, the sheath 174, and the stylets 190 a,bshown in FIGS. 12-17. The kit 210 shown in FIG. 18 also includes a fluidmanipulation device in the form of a syringe 212, which may bepre-filled with a fluid composition for use during a facet jointsynovial cyst surgical operation. The syringe 212 includes a fluidconnector 214 configured to engage with an end portion of the fluidconnection hubs 160 a,b to permit the syringe 212 to be used tomanipulate fluid through the lumen of a rotatable member 158. Such a kit210 may include multiple ones of such a fluid manipulation device as thesyringe 212, with different ones of such syringes 212 includingdifferent fluid compositions for use during a surgical operation. Forexample, a syringe 212 may be pre-filled with an irrigation liquid, suchas a saline solution, and another such syringe 212 may be pre-filledwith a fluid composition including an active component, for example acollagenase or a hyaluronidase, used to treat a facet joint synovialcyst. FIG. 19 illustrates an example facet joint surgical tool 218including assembled components from the kit 210, including the workingpieces 152 a,b, sheath 174 and syringe 212. The stylets 190 a,b are notincluded in the assembly of the surgical tool 218. As shown in FIG. 19,the rotatable members 158 a,b have relative positioning so that thedistal end portions 166 a,b are in a facet joint retractionconfiguration, similar to as shown in FIG. 17, but without the stylets190 a,b received through the working pieces 152 a,b and with the syringe212 fluidly connected with working piece 152 a through the fluidconnection hub 160 a to permit manipulation of fluid by the syringethrough the lumen of the rotatable member 158 a.

Reference is now made to FIGS. 20-28 illustrating some example surgicalprocedures using a facet joint surgical tool of this disclosure to treatan anterior facet joint synovial cyst. FIG. 20 shows a portion of afacet joint surgical tool 300 inserted through the skin 330 of a patientthrough tissue of the patient to a posterior side of a facet joint 302between a superior articular process 304 and an inferior articularprocess 306 of adjacent vertebrae. The synovial membrane, or synovium,308 secretes synovial fluid to lubricate the facet joint 302. A synovialcyst 310 is located to the anterior side of the facet joint 302 and isfluidly connected with the interior of the facet joint 302 through asmall opening through a neck 332. For illustration, the synovial cyst310 is depicted in FIG. 20 as a true cyst lined with synovial cells, butalternatively the synovial cyst 310 could be a pseudocyst formed intissue anterior to the synovium on the anterior side of the facet joint302. Shown in FIG. 20 is an inserted portion of the surgical tool 300including a portion of a sheath 316 having disposed therethrough tworotatable members 318 and 320 with distal end portions 322 and 324configured to form a piercing tip. As shown in FIG. 20, the piercing tipof the facet joint surgical tool 300 has been advanced to a point wheredistal tips 326 and 328 of the rotatable members 318 and 320 projectinto the facet joint 302 from the posterior side. The facet jointsurgical tool 300 may, for example, be the facet joint surgical tool 200configured in the facet joint penetration configuration as shown in FIG.16, or may be of a different design. In a preferred implementation, whenpenetrating through tissue to the facet joint 302, the surgical tool 300may be configured with stylets disposed through lumens of the rotatablemembers 318 and 320 to close off distal ends of the lumens to preventtissue coring during tissue penetration.

FIG. 21 shows the facet joint surgical tool 300 at the same point ofadvancement as shown in FIG. 20, except that the rotatable members 318and 320 have been rotationally repositioned so that the distal endportions 322 and 324 are in a facet joint retraction configuration toretract the facet joint 302, to provide a larger opening through thefacet joint 302 for performance of medical procedures directed towardstreatment of the synovial cyst 310. The retraction may also help toincrease the opening through the neck 332 into the synovial cyst 310.Stylets through lumens of the rotatable members 318 and 320 may beremoved before or after rotating the rotatable members 318 and 320 toreconfigure the distal end portions 322 and 324 from the facet jointpenetration configuration to the facet joint retraction configuration.

FIG. 22 shows the facet joint surgical tool 300 advanced deeper into thefacet joint 302 to a point where the sheath 316 is jammed into the jointto keep the joint open, permitting the rotatable members to be moved,repositioned or removed from the sheath 316 as needed for performingmedical procedures while maintaining the facet joint 302 in a retractedposition. FIG. 23 shows the facet joint surgical tool 300 in the samepositioning as shown in FIG. 22, except with suction being appliedthrough the lumen of one or both of the rotatable member 318 and 320 toaspirate fluid that is amendable to aspiration from the facet joint 302and the synovial cyst 310. Aspiration is shown with the distal endportions 322 and 324 in the retraction configuration, but suchaspiration could also be performed with the distal portions positionedin the piercing configuration or in a different configuration. Becauseof the highly viscous nature of material in the facet joint 302 and thesynovial cyst 310, and the often restricted opening between the two,such aspiration may often not remove a significant amount of fluid orprovide enhancement of fluid communication into the facet joint 302 fromthe synovial cyst 310.

FIG. 24 shows the facet joint surgical tool 300 in the same position asshown in FIGS. 22 and 23, but with a fluid composition being injectedinto the facet joint 302 through the lumen of one or both of therotatable members 318 and 320. The fluid composition may include anactive component to help liquefy or to decompose tissue within the facetjoint 302 and/or the synovial cyst 310, such as for example ahyaluronidase or a collagenase. Fluid pressure from the fluid injectionalone or together with liquefying action of an active component in thefluid composition may help to improve fluid communication to thesynovial cyst 310. Such fluid pressure may alternatively be provided byinjecting irrigation liquid as the fluid composition, for example applyfluid pressure to help increase the fluid opening to the synovial cyst310 or even to rupture the synovial cyst 310.

When the fluid composition includes an active component to help liquefythe material within the synovial cyst, the procedure may be discontinuedfor a wait time to allow the action component time to work beforeattempting to further remove material from the synovial cyst 302.Following such a wait time after injecting such a fluid composition, thejoint may be aspirated, for example in a manner as shown in FIG. 23, toremove liquefied material, either due to viscosity reduction, such asthrough the addition of hyaluronidase, or through lower viscositymaterial resulting from digestion of tissue, for example using acollagenase. When using a collagenase, the tissue may alternatively benot aspirated and maybe left to digest and be removed by normalmetabolic activity. In addition to or as an alternative to aspiration ina manner as shown in FIG. 23, the facet joint 302 and synovial cyst 310may be irrigated with an irrigation liquid to help remove tissue fromthe synovial cyst 310, either before or after injection of a fluidcomposition such as shown in FIG. 24. In one variation, such an activefluid composition may be injected as shown in FIG. 23 and then aftersome wait time, the facet joint 302 and synovial cyst 310 may beirrigated with an irrigation liquid as shown in FIG. 25 to help flushreduced viscosity tissue from the synovial cyst 310 for removal throughthe rotatable member 320 while irrigation liquid is introduced throughthe other rotatable member 318.

Referring now to FIG. 26, the facet joint surgical tool 300 is shownfollowing treatment of the synovial cyst 310 and showing the synovialcyst 310 significantly reduced in size due to removal of material fromthe volume of the synovial cyst 310. In FIG. 25, the facet jointsurgical tool 300 has been withdrawn to a more posterior position atwhich one or both of the rotatable members 318 and 320 are used as a RFelectrode for performing a RF ablation procedure at the posterior edgeof the facet joint 302 to create an artificial cavity. For example, therotatable members 318 and 320 may be made of a metallic material (e.g.,stainless steel) useful for transmitting RF signals. The RF ablationprocedure ablates tissue at the posterior edge of the facet joint 302 tocreate an ablated tissue volume 340 to provide an artificial cavity toprovide a volume to receive excess synovial fluid as an alternative tosynovial cyst recurrence on the anterior side of the facet joint 302.Following creation of the artificial cavity of the ablated tissue volume340, the facet joint surgical tool 300 may be further withdrawn from thepatient.

Reference is now made to FIG. 27 in which the facet joint surgical tool300 has been further withdrawn to a more posterior location relative tothe ablated tissue volume 340. At this location, a further tissueablation procedure may be performed as shown in FIG. 27 to prepare asecond ablated tissue volume 342, such as by RF ablation that may againuse one or both of the rotatable members 318, and 320 as a RF electrodefor transmitting RF energy for the second ablation procedure. Thissecond RF ablation procedure may be targeted to destroy or significantlyimpair activity of the synovium located on the posterior side of thefacet joint 302, to reduce potential for generating synovial fluid thatcould fill the artificial cavity or that could migrate through the facetjoint 302 to the anterior side to promote recurrence of a synovial cyston the anterior side of the facet joint 302. After performing thissecond RF tissue ablation procedure, the facet joint surgical tool 300may be completely withdrawn from the patient, as shown in FIG. 28.

Referring now to FIG. 29, an example is shown of a facet joint surgicaltool with one of the rotatable members connected to a RF signal sourcefor use of the rotatable member as a RF electrode for performing a RFablation procedure. As shown in FIG. 29, a facet joint surgical tool 400includes two rotatable members 402 and 404 constrained in a side-by-siderelationship through a sheath 406. The rotatable member 404 iselectrically connected through an electrical connector 408 with a RFsignal generator 410 to provide a RF signal to the rotatable member 402to be transmitted to a distal end of the rotatable member 402 to emit RFenergy for RF tissue ablation.

Any feature of any aspect or any embodiment disclosed herein may becombined in any combination with any feature or features of any otheraspect(s) or embodiments(s), and may be applied in like manner totreatment of synovial cysts at synovial joints other than the facetjoints.

The foregoing discussion of the invention and different aspects thereofhas been presented for purposes of illustration and description. Theforegoing is not intended to limit the invention to only the form orforms specifically disclosed herein. Consequently, variations andmodifications commensurate with the above teachings, and the skill orknowledge of the relevant art, are within the scope of the presentinvention. The embodiments described hereinabove are further intended toexplain best modes known for practicing the invention and to enableothers skilled in the art to utilize the invention in such, or other,embodiments and with various modifications required by the particularapplications or uses of the present invention. It is intended that theappended claims be construed to include alternative embodiments to theextent permitted by the prior art. Although the description of theinvention has included description of one or more possibleimplementations and certain variations and modifications, othervariations and modifications are within the scope of the invention,e.g., as may be within the skill and knowledge of those in the art afterunderstanding the present disclosure. It is intended to obtain rightswhich include alternative embodiments to the extent permitted, includingalternate, interchangeable and/or equivalent structures, functions,ranges or steps to those claimed, whether or not such alternate,interchangeable and/or equivalent structures, functions, ranges or stepsare disclosed herein, and without intending to publicly dedicate anypatentable subject matter. Furthermore, any feature described or claimedwith respect to any disclosed implementation may be combined in anycombination with one or more of any other features of any otherimplementation or implementations, to the extent that the features arenot necessarily technically incompatible, and all such combinations arewithin the scope of the present invention.

The terms “comprising”, “containing”, “including” and “having”, andgrammatical variations of those terms, are intended to be inclusive andnonlimiting in that the use of such terms indicates the presence of somecondition or feature, but not to the exclusion of the presence also ofany other condition or feature. The use of the terms “comprising”,“containing”, “including” and “having”, and grammatical variations ofthose terms in referring to the presence of one or more components,subcomponents or materials, also include and is intended to disclose themore specific embodiments in which the term “comprising”, “containing”,“including” or “having” (or the variation of such term) as the case maybe, is replaced by any of the narrower terms “consisting essentially of”or “consisting of” or “consisting of only” (or the appropriategrammatical variation of such narrower terms). For example, a statementthat some thing “comprises” a stated element or elements is alsointended to include and disclose the more specific narrower embodimentsof the thing “consisting essentially of” the stated element or elements,and the thing “consisting of” the stated element or elements. Examplesof various features have been provided for purposes of illustration, andthe terms “example”, “for example” and the like indicate illustrativeexamples that are not limiting and are not to be construed orinterpreted as limiting a feature or features to any particular example.The term “at least” followed by a number (e.g., “at least one”) meansthat number or more than that number. The term “at least a portion”means all or a portion that is less than all. The term “at least a part”means all or a part that is less than all.

The features in the drawings are shown for illustration purposes and togenerally show relative positioning and interaction, and the featuresshown are not necessarily to scale and depictions may not be complete inevery detail.

What is claimed is:
 1. A facet joint surgical tool, comprising: aproximal portion configured to be disposed outside of a patient during afacet joint surgical procedure; a distal portion configured to bedisposed inside of a patient during a facet joint surgical procedure; afirst rotatable member comprising a first distal end portion having afirst distal tip, the first rotatable member being rotatable about afirst axis; and a second rotatable member comprising a second distal endportion having a second distal tip, the second rotatable member beingrotatable about a second axis that is different than the first axis; andthe first and second rotatable members being rotatable relative to eachother about the first and second axes respectively to manipulate therelative positioning of the first and second distal end portions betweena facet joint penetration configuration in which the first and seconddistal end portions are positioned to form a piercing tip to piercethrough tissue and penetrate into the facet joint and a facet jointretraction configuration in which the first and second distal endportions are positioned to retract the facet joint following penetrationinto the facet joint; and wherein: when the said rotatable members arein the facet joint penetration configuration, the distal tips areadjoining; when the said rotatable members are in the facet jointretraction configuration, the distal tips are separated by a separationdistance in the range of from 0.5 millimeter to 6.5 millimeters; eachsaid rotatable member comprises a longitudinally extending insertionportion configured for insertion into the body during a surgicaloperation; the insertion portion has a longitudinal length in a range offrom 20 millimeters to 200 millimeters and a maximum cross dimensionperpendicular to the respective axis of rotation of no larger than 3.25millimeters; the insertion portion of each said rotatable member has alongitudinally extending lumen configured to provide access from outsideof the body to inside of the body during a surgical procedure; each saidlumen has a maximum cross dimension in a range of from 0.25 millimeterto 2.5 millimeters; and each said lumen has a longitudinal length of atleast 10 millimeters.
 2. A facet joint surgical tool according to claim1, wherein: the facet joint surgical tool comprises a sheath with aninternal passage through which the said rotatable members are disposedwith at least said distal tips disposed distal to a distal end of thesheath; the internal passage has a minimum area cross-section throughwhich the said rotatable members are disposed that has an aspect ratio,the aspect ratio of the minimum area cross-section being a ratio of alength dimension of the minimum area cross-section to a width dimensionof the minimum area cross-section, with the length dimension of theminimum area cross-section being a maximum cross dimension of theminimum area cross-section and the width dimension being a maximum crossdimension of the minimum area cross-section perpendicular to the lengthdimension of the minimum area cross-section; the aspect ratio of theminimum area cross-section is at least 1.5:1, whereby the minimum areacross-section is of non-circular shape; the length dimension of theminimum area cross-section is in a range of from 0.5 millimeter to 6.5millimeters; the minimum area cross-section is sized to constrain thesaid rotatable members in a side-by-side orientation through the minimumcross-section, in which side-by-side orientation the said rotatablemembers are translatable through the minimum area cross-section in alongitudinal direction through the internal passage; and the sheath hasa longitudinally extending insertion portion for insertion into apatient's body during a surgical operation, the insertion portion of thesheath having a longitudinal length of at least 10 millimeters andhaving disposed therethrough at least a portion of the insertionportions of the said rotatable members.
 3. A facet joint surgical toolaccording to claim 2, wherein: the insertion portion of the sheath hasan insertion cross-section with an aspect ratio, the aspect ratio of theinsertion cross-section being a ratio of a length dimension of theinsertion cross-section to a width dimension of the insertioncross-section, with the length dimension of the insertion cross-sectionbeing a maximum cross dimension of the insertion cross-section and thewidth dimension being a maximum cross dimension of the insertioncross-section perpendicular to the length dimension of the insertioncross-section; the aspect ratio of the insertion cross-section is atleast 1.5:1, whereby the insertion cross-section is of non-circularshape; and the length dimension of the insertion cross-section is in arange of from 0.7 millimeter to 8 millimeters.
 4. A facet joint surgicaltool according to claim 3, wherein: each said lumen of each saidrotatable member is fluidly connected with a fluid connection hub thatis connectable with a fluid manipulation device to perform a fluidmanipulation selected from the group consisting of fluid injectionthrough the said lumen out of a distal end of the said lumen adjacentthe corresponding distal tip and fluid aspiration through the said lumenthe distal end of the said lumen.
 5. A facet joint surgical toolaccording to claim 3, wherein at least the first rotatable memberincludes an arcuate portion, the arcuate portion being located proximalof a proximal end of the sheath.
 6. A facet joint surgical toolaccording to claim 3, wherein: the sheath has a tapered distal endportion with an exterior cross-section that tapers to a smaller sizetoward a distal end of the sheath; wall thickness of the sheathdecreases toward the distal end of the sheath in the tapered distal endportion; and in the tapered distal end portion the internal passagethrough the sheath does not taper to a smaller size toward the distalend of the sheath.
 7. A facet joint surgical tool according to claim 3,wherein: the said rotatable members are positioned in the facet jointpenetration configuration; and the tool includes a stylet disposedthrough each said lumen with distal tips of the stylets blocking distalends of the lumens.
 8. A facet joint surgical tool according to claim 3,comprising: a first rotation actuation handle connected to the firstrotatable member and hand manipulable to rotate the first rotatablemember about the first axis; and a second rotation actuation handleconnected to the second rotatable member and hand manipulable to rotatethe second rotatable member about the second axis.
 9. A kit useful inperformance of a medical procedure in the vicinity of a facet joint, thekit comprising: a first rotatable member comprising a first distal endportion having a first distal tip, the first rotatable member beingrotatable about a first axis of the first rotatable member; a secondrotatable member comprising a second distal end portion having a seconddistal tip, the second rotatable member being rotatable about a secondaxis of the second rotatable member; a sheath with an internal passagethrough which the said rotatable members are receivable with the distaltips of the said rotatable members disposed distal to a distal end ofthe sheath and proximal ends of the said rotatable members disposedproximal of a proximal end of the sheath, and wherein when so receivedthrough the sheath the first and second rotatable members are rotatablerelative to each other about the first and second axes respectively tomanipulate the relative positioning of the first and second distal endportions between a facet joint penetration configuration in which thefirst and second distal end portions are positioned to form a piercingtip to pierce through tissue and penetrate into the facet joint and afacet joint retraction configuration in which the first and seconddistal end portions are positioned to retract the facet joint followingpenetration into the facet joint; the internal passage of the sheathhaving a minimum area cross-section through which the said rotatablemembers are receivable that has an aspect ratio, the aspect ratio of theminimum area cross-section being a ratio of a length dimension of theminimum area cross-section to a width dimension of the minimum areacross-section, with the length dimension of the minimum areacross-section being a maximum cross dimension of the minimum areacross-section and the width dimension being a maximum cross dimension ofthe minimum area cross-section perpendicular to the length dimension ofthe minimum area cross-section; the aspect ratio of the minimum areacross-section is at least 1.5:1, whereby the aspect ratio of the minimumarea cross-section is non-circular; and the minimum area cross-sectionis sized to constrain the said rotatable members in a side-by-sideorientation through the minimum area cross-section with the saidrotatable members being translatable through the minimum areacross-section in a longitudinal direction through the internal passage;and wherein: the length dimension of the minimum area cross-section isin a range of from 0.5 millimeter to 6.5 millimeters; each saidrotatable member has a longitudinally extending insertion portion forinsertion into a patient's body during a surgical operation and whichinsertion portion is receivable through the internal passage of thesheath; each said insertion portion of each said rotatable member has alongitudinal length in a range of from 20 to 200 millimeters; each saidinsertion portion of each said rotatable member has a maximum crossdimension perpendicular to the respective axis of rotation of no largerthan 3.25 millimeters; when the said rotatable members are in the facetjoint penetration configuration, the distal tips of the distal endportions are adjoining; and when the said rotatable members are in thefacet joint retraction configuration, the distal tips of the distal endportions are separated by a separation distance in a range of from 0.5millimeters to 6.5 millimeters.
 10. A kit according to claim 9, whereineach said insertion portion of each said rotatable member has alongitudinally extending lumen to provide access from outside of apatient's body to inside of a patient's body during a surgicalprocedure.
 11. A kit according to claim 10, wherein the sheath has alongitudinally extending insertion portion for insertion into apatient's body, the insertion portion including a distal end of thesheath and further comprising: a longitudinal length of at least 10millimeters; and an insertion cross-section with an aspect ratio, theaspect ratio of the insertion cross-section being a ratio of a lengthdimension of the insertion cross-section to a width dimension of theinsertion cross-section, with the length dimension of the insertioncross-section being a maximum cross dimension of the insertioncross-section and the width dimension being a maximum cross dimension ofthe insertion cross-section perpendicular to the length dimension of theinsertion cross-section; the aspect ratio of the insertion cross-sectionis at least 1.5, whereby the insertion cross-section is of non-circularshape; and the length dimension of the insertion cross-section is nolarger than 8 millimeters.
 12. A kit according to claim 11, wherein theinsertion portion of the sheath has a tapered distal end portion with anexterior cross-section that tapers to a smaller size toward a distal endof the sheath.
 13. A kit according to claim 11, wherein at least thefirst rotatable member includes an arcuate portion, the arcuate portionbeing located proximal of a proximal end of the sheath when the firstrotatable member is received in the internal passage of the sheath withthe first distal tip disposed distal of the distal end of the sheath.14. A kit according to claim 13, wherein the second rotatable memberdoes not include an arcuate portion.
 15. A kit according to claim 11,comprising: a first rotation actuation handle connected to the firstrotatable member and hand manipulable to rotate the first rotatablemember about the first axis; and a second rotation actuation handleconnected to the second rotatable member and hand manipulable to rotatethe second rotatable member about the second axis; and wherein, when thefirst and second said rotatable members are received through theinternal passage of the sheath with the first and second distal tipsdisposed distal of the distal end of the sheath, the first and secondrotation actuation handles are disposed proximal of a proximal end ofthe sheath.
 16. A kit according to claim 15, wherein when the first andsecond distal tips are conterminous at distal ends of the said rotatablemembers conterminously disposed distal of the distal end of the sheath,the locations of connection of the first and second handles with thefirst and second rotatable members are at corresponding longitudinallocations along the first and second rotatable members.
 17. A kitaccording to claim 11, comprising first and second stylets receivablethrough the lumen of the first rotatable member and the second rotatablemember, respectively, with the said stylets including distal tips thatblock distal ends of the lumens adjacent the piercing tip in the facetjoint penetration configuration.